As an image source for projecting an image onto a reflection screen, there have widely been used, for example, short focus type image projection devices (projectors) which project image light from a very short distance at a comparatively large angle of incidence so as to realize a large screen display.
Such a short focus type image projection device can project image light onto a reflection screen from above or below at a larger incidence angle, as compared with image sources according to the related art. In addition, the distance between the image projection device and the reflection screen in the depth direction can be shortened. Therefore, the short focus type image projection device can contribute to space saving or the like in an image display system using a reflection screen.
In order to achieve favorable display of the image light projected by such a short focus type image projection device, there have been developed various reflection screens and the like which include a reflection layer formed on the surface of a lens layer having a linear Fresnel lens shape or circular Fresnel lens shape composed by arraying a plurality of unit lenses (see, for example, Japanese Patent Laid-Open No. 2008-76523, hereinafter referred to as Patent Document 1).